[{"key":"dc.contributor.author","value":"Cho, Yeong-Bong","language":""},{"key":"dc.date.accessioned","value":"2009-07-10T00:00:00","language":""},{"key":"dc.date.available","value":"2009-07-10T00:00:00","language":null},{"key":"dc.date.issued","value":"2000","language":null},{"key":"dc.identifier.uri","value":"http:\/\/hdl.handle.net\/2429\/10582","language":""},{"key":"dc.description.abstract","value":"DP (Dual-Phase) and TRIP (Transformation Induced Plasticity) steels, also known as multiphase\r\nsteels, have been attracting a growing interest in the development of lighter\r\nautomobiles owing to their excellent combination of strength and ductility. TRIP steels can\r\nusually be generated from a standard cold-rolled ferrite-pearlite grade by a two stage\r\ncontinuous annealing process; continuous heating and intercritical annealing, followed by\r\nsubsequent cooling and austempering. The material is first intercritically annealed in the\r\nferrite\/ austenite coexistence region, during which the ferrite matrix recrystallizes and\r\naustenite is created. Austempering is then performed and some upper bainite is formed,\r\nwhich, in turn, stabilizes the remaining austenite even down to room temperature.\r\nMost studies have been focused so far on the second stage of the thermal scheme due to the\r\nfact that the steel properties depend primarily on the transformation processes following\r\naustenitization. However, the phase transformations occurring upon heating is of profound\r\nimportance. The state of the microstructure after heating; i.e., volume fraction, shape,\r\ndistribution and chemical composition of the austenite grains, has a great influence on the\r\nkinetics of the phase transformation during cooling and on the subsequent mechanical\r\nproperties of the steel. Furthermore, the kinetics of the reverse transformation to austenite\r\n\r\ndetermine the time and temperature required for either intercritical heat treatment or\r\nnormalization.\r\nThe objective of the present study is to characterize and understand the reaustenitization\r\nkinetics from pearlite-ferrite structure during continuous heating. Futher, a mathematical\r\nmodel based on the Avrami equation and the additivity principle has been adopted in\r\nmodeling the pearlite-ferrite to austenite transformation during continuous heating.","language":"en"},{"key":"dc.format.extent","value":"8084291 bytes","language":""},{"key":"dc.format.mimetype","value":"application\/pdf","language":""},{"key":"dc.language.iso","value":"eng","language":"en"},{"key":"dc.publisher","value":"University of British Columbia","language":null},{"key":"dc.rights","value":"For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https:\/\/open.library.ubc.ca\/terms_of_use.","language":null},{"key":"dc.title","value":"The kinetics of austenite formation during continuous heating of a multi-phase steel","language":"en"},{"key":"dc.type","value":"Text","language":""},{"key":"dc.degree.name","value":"Master of Applied Science - MASc","language":"en"},{"key":"dc.degree.discipline","value":"Materials Engineering","language":"en"},{"key":"dc.degree.grantor","value":"University of British Columbia","language":""},{"key":"dc.date.graduation","value":"2000-11","language":"en"},{"key":"dc.type.text","value":"Thesis\/Dissertation","language":"en"},{"key":"dc.description.affiliation","value":"Applied Science, Faculty of","language":null},{"key":"dc.description.affiliation","value":"Materials Engineering, Department of","language":null},{"key":"dc.degree.campus","value":"UBCV","language":"en"},{"key":"dc.description.scholarlevel","value":"Graduate","language":"en"}]